In the case of a current architectural structure constructed using pillar and beam structures, a light-weight frame member can be used to make the pillars. The resulting architectural structure has an increased space, an excellent heat isolation ability and a strong moisture-prevention capability, to thus provide a comfortable housing environment. However, the manufacturing of the existing pillar and beam structures is a complicated construction process. That is, the manufacturing of the pillars and beams from respective connection portions requires a welding of the portions together, which impedes an efficient assembly. Also, it is not easy to maintain heat isolation at the beam and pillar connection sections. As a result, it is very difficult to prevent a moisture formation and to maintain a refractory performance.
For example, in the case of a house made of a conventional steel frame I-beam structure, an I-beam having a wide flange “a” is used as a pillar as shown in FIG. 16. In order to connect I-beam “a” used as a pillar with an I-beam “b” used as a beam, the beam must be welded to the pillar away from the construction site, and then the welded I-beam structure must be transported from the welding place to a construction site. In the case where the structure itself is large in size, it is difficult to transport the I-beam structure because it may be damaged during transportation, and a somewhat difficult welding job may be required during construction on site, which causes a difficult construction. Further, it is expensive to purchase pillar and beam structures and assembly components thereof.
Also, there is a problem in a connection structure that connects a pillar to a beam together as well as in an existing pillar and beam structures, where the connection structure is a wide flange abutting an external structure that is integrally connected with an internal structure. This problem is the formation and accumulation of moisture Accordingly, in order to prevent moisture formation, all portions abutting the external structure should be wrapped with a heat isolation material. This moisture problem and the use of heat isolation material results in a steel frame structure being expansive, and in turn resulting in an expansive architectural building. The expansive or enlarged building has a resulting external appearance that is unsightly and thus does not present a steel structure architecture having a light and nimble appearance.